1.Prenatal ultrasound manifestations and postnatal follow-up of fetuses with 22q11.2 microdeletion syndrome.
Xiaofei LIU ; Ya'nan WANG ; Tizhen YAN ; Shengli ZHANG ; Yanchuan XIE ; Jiwu LOU ; Hongwei JIANG
Chinese Journal of Medical Genetics 2026;43(1):31-35
OBJECTIVE:
To explore the prenatal and postnatal phenotypes of 22q11.2 microdeletion syndrome (22q11.2DS) and enhance clinical understanding of this condition.
METHODS:
Data were collected from 86 fetuses diagnosed with 22q11.2DS at four prenatal diagnostic centers across China between January 2014 and August 2025. Prenatal imaging findings, pregnancy outcomes, and postnatal conditions were analyzed.
RESULTS:
Among the 86 fetuses, complete ultrasound data were available for 65 cases. Cardiovascular abnormalities were observed in 42 cases, thymic hypoplasia or aplasia in 7 cases, urinary system anomalies in 6 cases, nuchal translucency (NT) thickening in 7 cases, butterfly vertebrae, clubfoot, omphalocele and diaphragmatic hernia in 1 case each, cleft lip and palate in 2 cases, and ultrasound soft markers in 13 cases. The parents of 9 fetuses opted to continue with the pregnancy. Among these, 6 showed no significant ultrasound abnormalities and no related phenotypes postnatally, while the remaining 3 exhibited ultrasound anomalies with postnatal manifestations including developmental delay, immunodeficiency, and cardiac defects.
CONCLUSION
Fetuses with 22q11.2DS may exhibit various ultrasound abnormalities in multiple systems before and after birth. In addition to cardiovascular anomalies, they may also present with thymic hypoplasia or aplasia, thickened NT, and urinary abnormalities. Fetuses with thickened NT or thymic anomalies should be closely monitored, and thymic assessment should be included in routine prenatal imaging evaluations. For fetuses with 22q11.2DS who show no ultrasound abnormalities, the risk of developing severe phenotypes after birth is relatively low, but occult palate clefts and psychiatric disorders cannot be ruled out. Due to limitations in sample size and follow-up duration, above conclusions require further validation through large-scale prospective studies.
Humans
;
Female
;
Pregnancy
;
Ultrasonography, Prenatal
;
DiGeorge Syndrome/genetics*
;
Adult
;
Male
;
Follow-Up Studies
;
Fetus/diagnostic imaging*
;
Phenotype
;
Infant, Newborn
2.Genetic analysis and prenatal diagnosis of structural brain abnormalities associated with TUBB gene c.155A>G variant.
Yifan LIU ; Wei SONG ; Xinlian WANG ; Yan RUAN ; Meng ZHANG ; Yujiao CHEN ; Yan LIU ; Puqing ZHANG ; Li WANG ; Yousheng YAN
Chinese Journal of Medical Genetics 2026;43(2):136-142
OBJECTIVE:
To explore the genotype-phenotype correlation in a Chinese family with structural brain abnormalities due to variant of the TUBB gene.
METHODS:
A family undergoing prenatal diagnosis at Beijing Obstetrics and Gynecology Hospital in October 2024 was selected as the study subject. Clinical data were collected. Amniotic fluid sample was subjected to chromosomal copy number variation sequencing (CNV-seq). Trio whole-exome sequencing (Trio-WES) was carried out on the amniotic fluid and parental blood samples, and candidate variant was verified by Sanger sequencing. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: 2023-KY-076-01).
RESULTS:
Both prenatal ultrasound and fetal MRI showed deviation of brain midline, unilateral lateral ventriculomegaly, and bilateral gyral asymmetry. Trio-WES revealed that the fetus has harbored a maternally derived heterozygous missense variant of the TUBB gene [NM_178014.4: c.155A>G (p.N52S)]. Sanger sequencing confirmed that the woman and a previously terminated fetus both harbored the same variant. Both the proband and two fetuses exhibited similar neuroimaging abnormalities including midline deviation and asymmetrical gyri. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as likely pathogenic (PM2_Supporting+PS2_Moderate+PS3).
CONCLUSION
The heterozygous c.155A>G (p.N52S) variant was the TUBB gene probably underlay the pathogenesis of the structural brain abnormalities in this family. Above findings have expanded the phenotypic spectrum associated with the variant and facilitated the prenatal diagnosis for this family.
Humans
;
Female
;
Pregnancy
;
Prenatal Diagnosis
;
Tubulin/genetics*
;
Adult
;
Brain/diagnostic imaging*
;
Male
;
Pedigree
;
DNA Copy Number Variations/genetics*
;
Exome Sequencing
;
Genetic Association Studies
;
Magnetic Resonance Imaging
3.Genetic analysis of a de novo EFTUD2 variant causing Mandibulofacial dysostosis with microcephaly in a fetus.
Jianyu REN ; Xiaojiao GUAN ; Shuang LIU ; Yousheng YAN ; Shufa YANG
Chinese Journal of Medical Genetics 2026;43(4):288-294
OBJECTIVE:
To investigate the genetic etiology of a fetus diagnosed with Mandibulofacial dysostosis with microcephaly (MFDM).
METHODS:
A fetus that underwent prenatal diagnosis at Beijing Obstetrics and Gynecology Hospital, Capital Medical University, on May 19, 2025 was selected for analysis. Results of fetal ultrasound findings, chromosomal karyotyping, copy number variation sequencing (CNV-seq), and whole-exome sequencing (WES) were collected. Sanger sequencing was performed for familial validation of the pathogenic variant. The Human Protein Atlas (HPA), STRING, and Simple ClinVar databases were queried to characterize the biological features of the candidate gene. Three-dimensional structures of the wild-type and variant proteins were modeled and analyzed, and the evolutionary conservation of the affected amino acid was assessed using UGENE. Prenatal phenotypes associated with EFTUD2 variants were summarized through a review of the literature. This study was approved by the Ethics Committee of Beijing Obstetrics and Gynecology Hospital, Capital Medical University (Ethics No.: 2025-KY-029-01).
RESULTS:
At 23+2 weeks of gestation, ultrasound examination revealed bilateral microtia with low-set ears, mild micrognathia with a reduced mandibular-facial angle, a single umbilical artery, a slightly narrow aortic diameter, and trivial mitral regurgitation. Amniotic fluid karyotyping and CNV-seq showed no abnormalities. WES identified a de novo, previously unreported EFTUD2 variant, c.698dupA (p.V235Gfs*27), in the fetus. This frameshift variant is predicted to alter the structural integrity of the EFTUD2 protein. Literature review indicated that micrognathia and microtia or low-set ears are the most common sonographic features in fetuses with EFTUD2 variants, while secondary findings may include abnormal stomach bubble, cleft palate, single umbilical artery, gastrointestinal atresia, polyhydramnios, and reduced aortic diameter.
CONCLUSION
The EFTUD2: c.698dupA (p.V235Gfs*27) variant is likely the genetic cause underlying MFDM in this fetus.
Humans
;
Mandibulofacial Dysostosis/diagnostic imaging*
;
Microcephaly/diagnostic imaging*
;
Female
;
Pregnancy
;
Ribonucleoprotein, U5 Small Nuclear/chemistry*
;
Peptide Elongation Factors/chemistry*
;
Fetus
;
DNA Copy Number Variations/genetics*
;
Adult
;
Ultrasonography, Prenatal
4.Diagnostic and Therapeutic Role of Endoscopic Ultrasound (EUS) in a CT-Negative Occult Insulinoma
Chee Kit Tee ; Yong Siang Ng ; Noor Hafis Md Tob ; Norhaliza Mohd Ali
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):87-88
Introduction:
A negative computed tomography (CT) scan does not
preclude an insulinoma, as small lesions frequently remain
undetected on conventional imaging. This case highlights
the indispensable role of endoscopic ultrasound (EUS)—
not just for localizing occult tumors, but as a definitive,
minimally invasive therapeutic alternative to high-risk
surgical resection.
Case:
A 39-year-old female with underlying hypertension
presented with a 5-month history of predominantly fasting
hypoglycemia (glucose <3.0 mmol/L) and neuroglycopenic
symptoms, fulfilling Whipple’s triad. A supervised 72-hour
fast confirmed endogenous hyperinsulinemic hypoglycemia
at 31 hours, with a nadir glucose of 1.4 mmol/L, insulin
116 pmol/L, and C-peptide 821 pmol/L. Notably, contrastenhanced CT of the pancreas was reported as normal. To
overcome this, EUS was performed, successfully identifying
a hidden 19 × 18 mm lesion in the head of the pancreas,
intimately abutting the main pancreatic duct.
Despite medical therapy with diazoxide and strict dietary
modifications, her hypoglycemia remained refractory.
Given the tumor’s proximity to the main pancreatic duct,
surgical enucleation carried a prohibitively high risk of complications. Consequently, she underwent EUS-guided
radiofrequency ablation (RFA). Immediate post-procedure
outcomes demonstrated near-complete resolution of the
hypoglycemic episodes. Diazoxide was subsequently
stopped. Outpatient continuous glucose monitoring
confirmed sustained normoglycemia and marked symptom
resolution, with no procedure-related complications.
Conclusion
The absence of a pancreatic lesion on CT demands persistent clinical suspicion in cases of biochemically proven
hypoglycemia. EUS remains paramount for detecting occult
lesions missed by standard imaging. Importantly, EUSRFA serves as a highly effective, tissue-sparing alternative
to surgical resection for insulinomas, especially when
conventional surgery poses prohibitive anatomical risks.
Insulinoma
;
Tomography, X-Ray Computed
5.Small Lesion, Big Impact: EUS Localization and Ablation of a CT-Occult Insulinoma
Tharshini Indrajothy ; Vanusha Devaraja ; Goh Qing Ci ; Tay Yang Zet ; Patricia Lee Siow Ping
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):96-
Introduction:
Insulinoma is a rare functioning pancreatic neuroendocrine
tumor and the most common cause of endogenous
hyperinsulinemic hypoglycemia. Although biochemical
confirmation is usually straightforward, tumor localization may be difficult when lesions are small and not detected
on conventional cross-sectional imaging. In such cases,
endoscopic ultrasound (EUS) plays an important role
in identifying occult lesions and facilitating definitive
treatment.
Case:
A 52-year-old female was admitted in April 2025 with
recurrent seizures secondary to hypoglycemia for 3
years, with increasing frequency over time. She fulfilled
Whipple’s triad, with documented capillary glucose of
1.8 mmol/L during an episode and symptom resolution
following glucose administration. A supervised prolonged
fasting test confirmed endogenous hyperinsulinemic
hypoglycemia, with plasma glucose 1.4 mmol/L, insulin 122
pmol/L, and C-peptide 1,010 pmol/L. Short Synacthen test
demonstrated adequate adrenal reserve. Due to persistent
hypoglycemia, she required high-dose diazoxide.
Contrast-enhanced computed tomography abdomen did
not reveal a pancreatic lesion but incidentally detected a
right ovarian teratoma. She underwent total abdominal
hysterectomy and bilateral salpingo-oophorectomy in
June 2025, with histopathology confirming a mature cystic
teratoma without malignancy. However, hypoglycemic
episodes persisted. Further evaluation with EUS in July
2025 identified a highly vascular isoechoic 8 × 8 mm lesion
in the pancreatic body. Fine-needle biopsy confirmed a
well-differentiated neuroendocrine tumor (WHO grade 1)
with Ki-67 index of 2%. She subsequently underwent EUSguided radiofrequency ablation in August 2025. Follow-up
EUS in December 2025 showed post-ablation change, and
her hypoglycemic episodes resolved completely, allowing
diazoxide to be discontinued.
Conclusion
This case highlights the diagnostic challenge of occult
insulinoma in the presence of negative conventional
imaging. EUS was pivotal for tumor localization and tissue
diagnosis, while EUS-guided radiofrequency ablation
provided effective minimally invasive treatment in a
carefully selected patient.
Insulinoma
;
Tomography, X-Ray Computed
6.Prenatal phenotype and genetic analysis of two fetuses with Bardet-Biedl syndrome.
Lingyi ZHANG ; Zhigang ZHANG ; Xingguang WANG ; Yanyan LI
Chinese Journal of Medical Genetics 2025;42(2):226-231
OBJECTIVE:
To carry out genetic testing on two fetuses with prenatal ultrasound finding of polydactyly and renal abnormalities to determine the underlying causes.
METHODS:
Two fetuses with structural abnormalities detected by prenatal ultrasound at Cangzhou People's Hospital in 2021 were selected as the study subjects. Genomic DNA was extracted from the muscle tissue of the abortus and peripheral blood samples from both parents. Whole-exome sequencing (WES) was conducted on the trio to detect the genetic variants. Quantitative PCR was used to validate the exonic deletions. This study has been approved by the Ethics Committee of Cangzhou People's Hospital (Ethics No.K2020-049).
RESULTS:
Prenatal ultrasound revealed postaxial polydactylies of fingers and toes and slightly enlarged kidneys with increased echogenicity in fetus 1, along with polydactyly of both hands, enlarged kidneys, and enhanced echogenicity of renal parenchyma in fetus 2. Trio-WES analysis revealed that fetus 1 has harbored a pathogenic c.1339G>A variant of the BBS1 gene, along with a heterozygous 426 bp deletion in the 11q13.2 region, which was unreported previously. The deletion has involved exons 10 and 11 of the BBS1 gene. The two variants were inherited from its mother and father, respectively. Fetus 2 was found to harbor a pathogenic c.539G>A variant and a likely pathogenic c.49G>A variant of the BBS10 gene, which were inherited from its mother and father, respectively. The c.49G>A variant has not been documented in databases and the literature.
CONCLUSION
Two rare fetuses with Bardet-Biedl syndrome have been diagnosed. Above finding has expanded the mutational spectrum of this syndrome and has important implications for genetic counseling for the affected families.
Humans
;
Bardet-Biedl Syndrome/diagnostic imaging*
;
Female
;
Pregnancy
;
Fetus/abnormalities*
;
Ultrasonography, Prenatal
;
Phenotype
;
Polydactyly/diagnostic imaging*
;
Exome Sequencing
;
Adult
;
Genetic Testing
;
Male
;
Prenatal Diagnosis
;
Group II Chaperonins/genetics*
;
Microtubule-Associated Proteins
7.Genetic analysis of a fetus with Farber lipogranulomatosis caused by ASAH1 gene variant.
Yingwen LIU ; Lulu YAN ; Yuxin ZHANG ; Chunxiao HAN ; Haibo LI
Chinese Journal of Medical Genetics 2025;42(2):232-237
OBJECTIVE:
To explore the clinical characteristics and gene variant of a fetus with Farber lipogranulomatosis caused by ASAH1 gene variant.
METHODS:
A fetus with Farber lipogranulomatosis caused by ASAH1 gene variant diagnosed at Women and Children's Hospital of Ningbo University in August 2024 was selected as the subject. Clinical data and abortion tissue samples of the fetus and peripheral blood samples of its parents were collected for whole exome sequencing (WES). Sanger sequencing validation and bioinformatics analysis were performed on candidate variants. This study was approved by Women and Children's Hospital of Ningbo University (Ethics No. EC2020-048).
RESULTS:
Generalized skin oedema, pericardial effusion, right pleural effusion and increased bowel echogenicity of the fetus were founded by prenatal ultrasound. WES revealed that the fetus has harbored a homozygous c.101C>A (p.Ser34Ter) variation in exon 2 of the ASAH1 gene. Sanger sequencing confirmed that both parents carry the heterozygous nonsense variation c.101C>A (p.Ser34Ter) in ASAH1 gene, which has not been included in databases such as HGMD, ClinVar, 1000 Genomes, ExAC, dbSNP, and gnomAD. Based on the Standards and Guidelines for the Interpretation of Sequence Variants of the American College of Medical Genetics and Genomics (ACMG), the variant was predicted to be pathogenic (PM2_Supporting+PVS1+PM3_Supporting). The AlphaFold3 model protein structure prediction reveals that the c.101C>A variant caused the premature appearance of a termination codon, resulting in only a small partial α-helix structure in the N-terminal of the encoded ASAH1 protein, with the complete loss of the α-helix structure in the core domain, which might lead to the loss of function of this protein.
CONCLUSION
The c.101C>A (p.Ser34Ter) variant of the ASAH1 gene probably underlay the Farber lipogranulomatosis with hydrops fetalis in this fetus. The newly discovered c.101C>A (p.Ser34Ter) variant has enriched the mutational spectrum of Farber lipogranulomatosis.
Humans
;
Female
;
Pregnancy
;
Acid Ceramidase/chemistry*
;
Farber Lipogranulomatosis/diagnostic imaging*
;
Fetus
;
Exome Sequencing
;
Adult
8.Clinical and genetic analysis of a Chinese pedigree with autosomal recessive familial intrahepatic cholestasis type I due to a novel variant of ATP8B1 gene.
Zhimin WANG ; Haili QI ; Xiaojuan WEI ; Hualing DUAN ; Xiaohuan LI ; Hongyang QI
Chinese Journal of Medical Genetics 2025;42(5):608-612
OBJECTIVE:
To investigate the clinical and genetic features of a Chinese pedigree with Progressive familial intrahepatic cholestasis (PFIC) and explore its genotype-phenotype correlation.
METHODS:
A patient with PFIC diagnosed at Xinxiang Central Hospital in 2023 was selected as the study subject. The patient was subjected to abdominal magnetic resonance imaging (MRI) and painless gastroscopy. Peripheral blood samples were collected from the patient and his parents for the extraction of genomic DNA and trio-whole exome sequencing (trio-WES). Candidate variants were verified by Sanger sequencing. This study has been approved by the Medical Ethics Committee of Xinxiang Hospital (Ethics No. 2023-241).
RESULTS:
MRI scan showed that the patient had significantly enlarged liver and spleen. WES revealed that he has harbored compound heterozygous variants of the ATP8B1 gene, including a c.1710_1711insCCTC (p.A571Pfs*12) frameshifting variant in exon 16 and a c.2989G>A (p.V997M) missense variant in exon 24, which were respectively inherited from his father and mother, and rated as pathogenic (PVS1+PM2_Supporting+PM3+PP1) and likely pathogenic (PM2_Supporting+PM3+PP1) based on the guidelines from the American College of Medical Genetics and Genomics (ACMG).
CONCLUSION
WES can clarify the genetic etiology of patients with speed and accuracy, and facilitate clinical decision-making. The detection of pathogenic variants has provided a basis for clinical diagnosis and enriched the mutational spectrum of the ATP8B1 gene.
Humans
;
Male
;
Pedigree
;
Cholestasis, Intrahepatic/diagnostic imaging*
;
Adenosine Triphosphatases/genetics*
;
Female
;
Adult
;
Exome Sequencing
;
Mutation
;
East Asian People
9.Clinical and genetic analysis of a patient with unilateral Pigmented paravenous retinochoroidal atrophy and Retinitis pigmentosa in the contralateral eye related to CRB1 gene variant.
Yongping TANG ; Hanshi HUANG ; Xiaoyan LIN ; Zailong CHI
Chinese Journal of Medical Genetics 2025;42(5):621-627
OBJECTIVE:
To explore the clinical phenotype, genotype and genetic characteristics for a patient with unilateral Pigmented paravenous retinochoroidal atrophy (PPRCA) and Retinitis pigmentosa (RP) in the contralateral eye.
METHODS:
A PPRCA pedigree which had presented at the Department of Medical Genetics of the Eye Hospital of Wenzhou Medical University in August 2021 was selected as the study subject. Clinical data of the family members were collected. The proband underwent wide-field fundus photography, wide-field autofluorescence, full-field electroretinogram (ff-ERG), visual field testing, optical coherence tomography (OCT), and fundus angiography (FFA and ICGA). Blood samples were collected from the proband and family members (parents and two sisters), and buccal mucosal cells were collected from the proband's daughter, and genomic DNA was extracted for each family member. Whole exome sequencing (WES) was performed on the proband. Candidate variants were verified using Sanger sequencing and pathogenicity analysis. This study was approved by the Medical Ethics Committee of the Eye Hospital of Wenzhou Medical University (Ethics No. 2019-134).
RESULTS:
Wide-angle fundus photography and autofluorescence showed that the right eye was consistent with PPRCA and the left eye with RP. OCT showed that the outer layer of the fovea was intact in the right eye, while disorganized outer segment was found in the fovea of the left eye, and outer segment atrophies outside the fovea were found in both eyes. The amplitudes of ff-ERG decreased significantly in both eyes, and the amplitudes in right eye were slightly higher than those of the left eye. Visual field showed a paracentral arcuate scotoma in the right eye and severe centripetal contraction in the left eye. FFA showed hyperfluorescence in the retinal vein distribution area caused by atrophy of retinal pigment epithelium of the right eye and hypofluorescence related to bone spicule pigmentation, in addition with mottled hypofluorescence of choroid in the left eye. ICGA showed mild paravenous retinochroidal atrophy of the right eye and diffuse choroid capillaries atrophy in the middle and peripheral area of the left eye. WES revealed that the proband had a heterozygous c.2234C>T (p.Thr745Met) variant of the CRB1 gene. Sanger sequencing confirmed that the proband and family members except the father of the proband carried the same CRB1 gene variant. Based on the criteria and guidelines for the classification of genetic variation and related consensus from the American College of Medical Genetics and Genomics (ACMG), this variant was classified as pathogenic (PM3_VeryStrong+PM1+PM2_Supporting +PP3).
CONCLUSION
The heterozygous c.2234C>T (p.Thr745Met) variant of the CRB1 gene may underlay the unilateral PPRCA with contralateral eye RP in this proband. Above findings have enriched the mutational spectrum of the CRB1 gene.
Humans
;
Electroretinography
;
Exome Sequencing
;
Eye Proteins/genetics*
;
Membrane Proteins/genetics*
;
Mutation
;
Nerve Tissue Proteins/genetics*
;
Pedigree
;
Phenotype
;
Retinitis Pigmentosa/genetics*
;
Tomography, Optical Coherence
;
Retinal Degeneration
;
Eye Diseases, Hereditary
10.Prenatal ultrasound and genetic characteristics of fetuses with Kabuki syndrome: A report of six cases and literature review.
Chinese Journal of Medical Genetics 2025;42(8):952-957
OBJECTIVE:
To explore the clinical and genetic characteristics of fetuses with Kabuki syndrome (KS) and their genotype-phenotype correlation.
METHODS:
A retrospective analysis was carried out on the prenatal manifestations and results of genetic testing of six KS fetuses diagnosed by whole-exome sequencing (WES). The findings were compared with 28 prenatally diagnosed KS cases reported in the literature to summarize the prenatal features of KS. This study has been approved by the Ethics Committee of Maternal and Child Health Care Hospital of Hubei Province (Ethics No.: 2025-141-01).
RESULTS:
Prenatal ultrasound findings in KS fetuses showed high heterogeneity. The most common abnormalities were cardiac (23/35, 65.7%) and renal (20/35, 57.1%), which are often accompanied by amniotic fluid abnormalities (5/35, 14.3%), single umbilical artery (5/35, 14.3%), and fetal hydrops (4/35, 11.4%). Among the six fetuses from our center, all were identified by WES to harbor pathogenic variants of the KMT2D gene, and all of which were de novo. These included 3 frameshift variants, 2 nonsense variant, and 1 missense variant, among which 4 were unreported previously.
CONCLUSION
This study has expanded the mutational spectrum of the KMT2D gene. Prenatal ultrasound findings of KS lack specificity, though multi-system anomalies or specific soft markers may indicate KS. WES is an effective tool for the diagnosis, and KS should be included in the differential diagnosis list for prenatal cardiac and renal abnormalities.
Humans
;
Hematologic Diseases/diagnostic imaging*
;
Face/diagnostic imaging*
;
Female
;
Vestibular Diseases/diagnostic imaging*
;
Abnormalities, Multiple/diagnostic imaging*
;
Pregnancy
;
Ultrasonography, Prenatal
;
Adult
;
Neoplasm Proteins/genetics*
;
Retrospective Studies
;
DNA-Binding Proteins/genetics*
;
Male
;
Exome Sequencing
;
Fetus/diagnostic imaging*
;
Genetic Association Studies
;
Mutation


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